This invention relates generally to process systems and methods for controlling the size of vegetable products or the like, particularly such as potatoes in the course of french fry strip production. More specifically, the present invention relates to a cutting system and method for cutting overlong raw or whole products in response to detected product length, to control finished product length distribution while minimizing or eliminating the presence of products which are too long or short.
Production equipment for processing and packaging elongated articles such as vegetable products or the like are generally known in the art. As one example, it is well-known to process potatoes through a sequence of peeling, cutting and parfrying steps to produce elongated french fry potato strips which are typically packaged in a frozen state. Natural variations in the length of the raw potato product, prior to strip cutting, yields a corresponding distribution of cut french fry strip lengths. Accordingly, some variation in the lengths of the product strips supplied to the consumer is expected and is perceived by the consumer as a desirable characteristic.
However, products of excessive length can contribute to production problems and/or negatively impact the consumer's perception of the finished product. In particular, with regard to production of french fry potato strips, so-called hydraulic or water knives of the type described in U.S. Pat. Nos. 2,108,625 and 4,372,184 are commonly used to cut raw whole potatoes into elongated french fry strips of selected cross sectional shape and size. In cutting equipment of this type, potatoes having excessive lengths can become lodged within the cutting knives and thereby interrupt the cutting process. Alternately, the cut surfaces on strips of excessive length can deteriorate to result in fragile and/or fractured strips which tend to break apart into small pieces upon subsequent process steps. The presence of a high proportion of extremely short strip pieces is perceived negatively by the consumer, suggesting that the french fry strips have been cut from small potatoes. Moreover, french fry strips of excessive length which do not break apart in the course of post-cutting processing unfortunately exhibit a tendency to bend or curl during parfrying and/or freezing, once again resulting in undesirable appearance characteristics in the finished product.
In the past, the above-referenced issues of product length distribution have been addressed in different ways. In a typical french fry production line, raw potatoes are commonly graded according to size to remove products of excessive length from the production line flow. In addition, size grading normally entails removal of a high percentage of relatively small potatoes, such that post-cutting breakage of longer strips does not result in an undesirably high proportion of short strip pieces. Alternatively, cutting systems have been proposed for cutting overlong products generally at a midpoint or at a fixed distance from one end of the product as described, for example in U.S. Pat. Nos. 3,291,173; 3,721,145; and 3,944,077. While such cutting systems beneficially reduce the occurrence of cut strips having excess length, the cutting techniques have not satisfactorily reduced the occurrence of an undesirable proportion of short potato strip pieces.
The present invention overcomes the problems and disadvantages encountered in prior art production systems, by providing an improved cutter system and method for variably cutting overlong products as a function of actual product length, thereby obtaining significant control over the length distribution of the finished product.